What is the meaning of the phrase "Indeed, the power of nature drives away and nullifies illness," and what is the nature referred to in it?

The intended meaning of "nature" in this context is the general disposition of a person and the health and physical strengths that Allah has endowed them with, which resist and repel illness. Ibn al-Qayyim mentioned that knowledge of the heart strengthens the soul and repels worries, just as physical nature strengthens in repelling sensory diseases. Ibn Muflih indicated that moderate sleep strengthens one's nature and relaxes the psychological faculties. Thus, "nature" expresses the pervasive force within bodies, which enables the body to reach its natural perfection. It is called such because Allah instilled it in humans at the origin of creation, and it is synonymous with the meanings of disposition (jibillah), creation (khalqah), and instinct (gharizah). Ibn Hajar clarified that the strength of certainty (yaqeen) and reliance on Allah (tawakkul) repels the belief in contagion, just as the strength of nature repels and nullifies illness, where a person with weak certainty is addressed by being told to keep away from places of contagion. Therefore, "nature" is the temperament and strength that Allah has placed in the body; if it is strong, it repels and nullifies disease.